Disinfectant and method of use

ABSTRACT

A non-toxic environmentally friendly aqueous disinfectant is disclosed for specific use as prevention against contamination by potentially pathogenic bacteria, fungi and virus. The aqueous disinfectant is formulated by electrolytically generating silver ions in water in combination with a citric acid. The aqueous disinfectant has many potential uses including bacteria, fungus and viral treatment, water treatment, medical treatment as well as for preserving consumable and non-consumable products.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 11/060,013,filed Feb. 16, 2005, U.S. Pat. No. 7,435,438 entitled “DISINFECTANT ANDMETHOD OF USE,” which is a continuation of application Ser. No.10/846,221, filed May 14, 2004, now abandoned which claims benefit ofProvisional Application No. 60/471,391 filed May 16, 2003, which arehereby incorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to disinfectants and more particularly to anenvironmentally friendly, non-toxic aqueous disinfectant formed byelectrolytically generating silver ions in water in combination with acitric acid.

2. Description of the Related Art

The prior art has demonstrated that the presence of copper and silverions in an aqueous solution is useful as a disinfectant. Many in theprior art have used copper and silver ions in an aqueous solution as adisinfectant in water systems such as cooling towers, swimming pools,hot water systems in hospitals, potable water systems, spa pools and thelike.

Typically, copper and silver electrodes were connected to a directcurrent power supply. When the direct current was applied to the copperand silver electrodes, copper and silver ions were generated by anelectrolysis process from the copper and silver ions within the water.In one example of the prior art, water was passed continuously throughan ion chamber having copper and silver electrodes. The water emanatingfrom the ion chamber contained the copper and silver ions generated bycopper and silver electrodes within the ion chamber. The water emanatingfrom the ion chamber containing the copper and silver ions was used as adisinfectant in water systems such as cooling towers, swimming pools,hot water systems in hospitals, potable water systems, spa pools and thelike. The copper and silver ions within the water systems acted as adisinfectant for controlling algae, viruses, bacteria and the like.

U.S. Pat. No. 3,422,183 to Ellison discloses biocide compositionscomprising ultra-violet irradiated silver fluoride solutions containingcolloidal silver resulting from the irradiation and kept in dispersionby a protective colloid, e.g., casein or gelatin, and biocide usesthereof in sline control, against pathogens or other microbes in food orbeverage containers or processing equipment, as an ingredient of woodpreservatives, as a bactericide in paints, as a biocide in syntheticpolymer films, as a sterilant in bandages, and biocide-like uses inother areas.

U.S. Pat. No. 3,702,298 to Zsoldos discloses a method of maintaining ahighly oxidizing aqueous solution intended primarily for treatment ofswimming pool water. A metal having a multiple valence is interacted toa lower valence with oxidizable debris in the solution, and the metal iscontinuously re-oxidized to a higher valence by maintaining in the watera constant excess of an oxidizer bank consisting of a salt of a peroxyacid. Silver, copper and nickel are suitable metals and their salts havegermicidal properties which are greatly increased and the spectrumbroadened by converting the mono salt to a divalent or trivalent salt.

U.S. Pat. No. 4,180,473 to Maurer et al. discloses a method oftransporting metal ions by introducing a metal complex into a mediumcontaining a moiety which demands the metal ion and the complex releasesthe ions in a controlled manner upon demand. The metal complexes have anaqueous proton induced dissociation property represented by asigmoidally-shaped curve on a cartesian coordinate plot of the negativelog of the metal ion concentration versus the negative log of hydrogenion concentration. This dissociation property causes a controlledrelease of metal ion into mediums containing a reacting moiety upondemand for the metal ion. For example, metal working emulsions of oiland water are stabilized by the addition thereto of minor amounts of ametal complex, e.g. disodium monocopper (II) citrate, which at alkalinepH metalworking conditions above about 7 to about 9 releases metalcatons to the emulsions imparting stabilizing characteristics whichprevent emulsion degradation by a number of factors commonly encounteredin metalworking operations. Also, the method is effective in thecontrolled release of metal ions in the normal range of physiologicalpH, i.e. about 4 to 9, for growth controlling action againstmicroorganisms including bacteria, fungi and viruses.

U.S. Pat. No. 4,291,125 to Greatbatch discloses a method and apparatusfor killing plant and animal bacteria and plant viroids by electricallygenerated silver ions. The silver ions serve as germicidal agents ininfection control and are generated by very slow electrical anodiccorrosion of a silver wire located closely adjacent the infection site.In particular, a silver anode and a cathode of non-corroding metal arelocated in an electrolytic nutrient medium with the silver anode beingwithin five millimeters of the infection site, and a direct voltage isapplied to the anode and cathode in a manner passing a positive currentin the microampere range into the silver anode causing it to corrodeslightly and give off silver ions which produce a germicidal environmentabout the infection site.

U.S. Pat. No. 4,385,632 to Odelhog discloses an absorbent body forcollecting blood, feces and urine containing a water-soluble copper saltwhich impedes bacterial growth, prevents the breaking-down of urea intoammonia and complex-binds ammonia so as to prevent the occurrence ofunpleasant odor. Preferably copper acetate is used, in which even theacetate ion has germicidal effect.

U.S. Pat. No. 4,564,461 to Skold et al. discloses mechanical working ofcast iron performed in the presence of an aqueous metal workingcomposition containing an organic copper (II) complex and an ironcorrosion inhibitor. An aqueous concentrate, which after dilution withwater is suitable for application in mechanical working of cast iron,contains 1-50% copper (II) complex with such a Cu₂+ content of 0.5-20%,1-50% iron corrosion inhibitor, 0-50% lubricant, 0-20% pH-regulators,bactericides and solubilizing agents and 10-70% water.

U.S. Pat. No. 4,608,183 to Rossmoore discloses antimicrobial mixtures ofisothiazolones and a metal complex with a polyfunctional ligand whichare synergistic. The mixtures particularly include mixtures of amonocopper disodium citrate as the ligand and a 5-x-2-lower alkyl4-isothiazolin-3-one wherein x is a halo or hydrogen group as theisothiazolone. The compositions are particularly useful for metalcutting fluids wherein long duration antimicrobial activity is desired.

U.S. Pat. No. 4,666,616 to Rossmoore discloses synergisticanti-microbial compositions containing a mixture of a metal complex of apolyfunctional organic liquid and a biocidal composition which containsor releases a lower aldehyde containing 1 to 5 carbon atoms. Thecompositions are particularly useful as metal working fluids at alkalinepH and have a broad spectrum of activity against fungi and bacterial.

U.S. Pat. No. 4,708,808 to Rossmoore discloses synergisticanti-microbial compositions containing a mixture of a metal complex of apolyfunctional organic ligand and a biocidal composition which containsor releases a lower aldehyde containing 1 to 5 carbon atoms. Thecompositions are particularly useful as metal working fluids at alkalinepH and have a broad spectrum of activity against fungi and bacteria.

U.S. Pat. No. 4,780,216 to Wojtowicz discloses a sanitizing compositionconsisting essentially of a mixture of a calcium hypochlorite compoundand a peroxydisulfate compound having the formula: M_(x)S₂O₈ where M isan alkali metal or alkaline earth metal, and x is 1 or 2 is employed intreating water to improve pH control and provide increased removal oforganic materials. The compositions provide improved sanitation of waterin swimming pools, spas, and cooling towers by efficiently oxidizingorganic impurities while helping to minimize the increase in the pH ofthe water. This permits a reduction in the amount and frequency ofaddition of acidic compounds such as hydrochloric acid to the waterbodies. Further, the incorporation of additives such as algaecides,dispersant, and clarifying agents provides for significant improvementsin water quality as evidenced by sparkling pure water.

U.S. Pat. No. 4,915,955 to Gomori discloses a concentrate with anunlimited shelf-life, which can be mixed with hydrogen peroxide at aratio of 1:99 to 1:199 to become an effective disinfectant, is obtainedwhen a viscous solution of inorganic acid, with a pH less than or equalto 1.6, is mixed with a silver salt compound or a colloidal silvercompound at 50° to 66° C. The mixture is further combined at roomtemperature with other inorganic acid(s) to reach a total of 100 ginorganic acid(s) per liter of water at room temperature, an organicacid stabilizer is added and the mixture is homogenize. The concentrate,during storage, remains homogeneous and crystal-clear.

U.S. Pat. No. 4,933,178 to Capelli discloses a medical device with anantimicrobial coating that is safe, effective, photostable and readilymanufacturable produced by applying a composition to at least one bodyfluid-contacting surface of the device such that a solid coating isprovided on that surface, the coating composition comprising anoligodynamic metal salt of a sulfonylurea, a polymeric material, atleast one acid compound selected from the group consisting of awater-soluble carboxylic acid and water-insoluble carboxylic acid, and acarrier liquid in which foregoing components are soluble. Theantimicrobial coating accommodates variation in the release ofantimicrobial metal ions as a function of the intended use for a medicaldevice to which the coating is applied.

U.S. Pat. No. 5,017,295 to Antelman discloses a method or methods ofcontrolling the growth of bacteria in the water of swimming pools and/orindustrial water supplies by adding to the water a specifiedconcentration of a stable divalent silver compound. The invention hasthe advantage over chlorination in that it is odorless and non-volatile.It furthermore is superior to monovalent silver compounds as thesecompounds do not decompose in the presence of light and resistprecipitation by halides and form divalent soluble complexes which inthe monovalent state are invariably insoluble solids.

U.S. Pat. No. 5,073,382 to Antelman discloses a solid alkalinebactericidal compositions suitable for compounding alkaline end productssuch as food and dairy cleaners and surgical scrubbing soaps, formed bythe neutralization of acid stabilized inorganic divalent silvercomplexes and capable of effecting 100% kills upon cultures of anaerobicbacteria colonies of 100K/cc. within 5 minutes.

U.S. Pat. No. 5,078,902 to Antelman discloses divalent silver halidesproviding a source for divalent bactericidal silver ions in the presenceof persulfate. The halides are especially effective when applied towater used in industrial cooling installations, hot tubs and swimmingpools and will conform to stringent EPA requirements for waters utilizedfor bathing as in tubs and pools of 100% kills of 100 K/cc E. Colicoliforms within 10 minutes, exemplary of which are the chloride andbromide which give 100% kills within 5 minutes. The halides, of course,can be used in salty water since they are solids immune from halideaction that would otherwise precipitate soluble divalent silver fromsolution.

U.S. Pat. No. 5,089,275 discloses solid bactericidal compositions basedon divalent silver (Ag(II)) as the active sanitized agent. Thecompositions are prepared by reacting acid liquid Ag(II) complexes withanhydrous calcium sulfate so as to form a solid matrix in which thebactericide is entrapped in the resulting hydrated calcium sulfate.Optimum compositions are described consisting of Ag(II) of solid (byweight) to liquid (by volume) is 5:2. The resulting solid bactericidescan be used in water cooling installations. They are capable of causing100% kills within 10 minutes of E. Coli conforms in conformity with EPAprotocols, allowing them to qualify as swimming pool and hot tubsanitizers. Since the compositions are based on calcium sulfate, theyare also suitable as mineralizers, thus providing a dual function.

U.S. Pat. No. 5,332,511 to Gay et al. discloses a process for sanitizingwater in swimming pools, spas and hot tubs whereby the level of bacteriain said water is lowered comprising treating said water with abactericidal effective amount of a combination of diisodecyl dimethylammonium chloride and copper (II) ions, the concentration of diisodecyldimethyl ammonium chloride in said water being less than about 60 partsper million parts of water by weight and treating said water at leastintermittently with an oxidant selected from the group consisting ofavailable chlorine and ozone.

U.S. Pat. No. 5,364,649 to Rossmoore et al. discloses activity ofantimicrobial compounds selected from isothiazolones and compounds whichrelease formaldehyde enhanced with a metal complex of a loweralkanolamine, particularly copper (cupric) trietha-iolamine. Theenhancement is particularly useful in metalworking fluids.

U.S. Pat. No. 5,373,025 to Gay discloses a sanitizer compositioncomprising a bactericidal effective amount of the combination of (a) aquaternary ammonium compound selected from the group consisting of(hydrogenated tallow) 2-ethylhexyl dimethyl ammonium salt, dicocodimethyl ammonium salt, and mixtures thereof; and (b) a copper (II) ionsource.

U.S. Pat. No. 5,382,337 to Wlassics et al. discloses a process foroxidizing organic materials or compounds in aqueous phase, with hydrogenperoxide and in the presence of ferrous ions FE-(II), and optionallycupric ions cu-(II), carried out under irradiation with artificialvisible light.

U.S. Pat. No. 5,464,559 to Marchin et al. discloses a compositionprovided for treating drinking water for disinfecting and/or removingiodide. The composition utilizes resin bound silver ions. For performingthe disinfection or iodide removal with minimal release of silver ionsinto the water being treated, a chelating resin having iminodiacetatechelating groups is employed, and the resin is loaded with not over 0.5mole of silver ions per mole of iminodiacetate.

U.S. Pat. No. 5,503,840 to Jacobson et al. discloses an antimicrobialcomposition of titanium dioxide, barium sulfate, zinc oxide particles,and mixtures thereof having successive coatings of silver, in some casesa coating of zinc and/or copper compounds such as zinc oxide, copper(II) oxide and zinc silicate; silicon dioxide; alumina; and a dispersionaid such as dioctyl azelate.

U.S. Pat. No. 5,510,109 to Tomioka et al discloses an antibacterial andantifungal composition which comprises an antibacterial and antifungalmaterial carried on a porous particle carrier. Preferably, the porousparticle carrier is a silica gel particle. The antibacterial andantifungal material is at least one metal complex salt, and can containplant extracts and the like in addition to the metal complex salt. Atleast a portion of the surface of the above-mentioned carrier having theantibacterial and antifungal composition can be coated with a coatingmaterial.

Unfortunately, these copper and silver ions within an aqueous solutionhave only a limited stable ionic life. After a limited time, the copperand silver ions form complexes with other elements thus diminishing theconcentration of the copper and silver ions within the aqueous solution.Accordingly, the aqueous solution had to be replenished with copper andsilver ions to maintain the concentration of the copper and silver ionswithin the aqueous solution. The aqueous solution may be replenishedwith copper and silver ions by constantly circulating the aqueoussolution thorough the ion chamber.

The present invention provides an aqueous disinfectant solution having astable ionic form having an extended useful shelf-life. The extendeduseful shelf-life of the aqueous disinfectant solution enables theaqueous disinfectant solution to be packaged in an aqueous concentrateform.

In my prior U.S. Pat. No. 6,197,814, I disclosed a novel disinfectantformulated by electrolytically generating silver ions in the presence ofcitric acid referred to a electrolytically generated silver citrate. Thecomplete text of my prior U.S. Pat. No. 6,197,814 is incorporated byreference into the present specification.

Therefore, it is an object of the present invention to provide new founduses for my novel disinfectant formulated by electrolytically generatingsilver ions in the presence of citric acid referred to aelectrolytically generated silver citrate.

Another object of this invention is to provide an improved disinfectantand the method of making which is an effective disinfectant foreliminating standard indicator organisms such as staphylococcus aureus,salmonella cholerasuis and pseudomonas aeruginosa.

Another object of this invention is to provide an improved disinfectantand the method of making which is a non-toxic, environmentally friendlyaqueous disinfectant.

Another object of this invention is to provide an improved disinfectantand the method of making which comprises a stable ionic formulationhaving an extended useful shelf-life.

Another object of this invention is to provide an improved disinfectantand the method of making which may be packaged in a concentrated aqueousform.

Another object of this invention is to provide an improved disinfectantand the method of making which may be electrolytically generated in abatch process or a continuous process.

Another object of this invention is to provide an improved disinfectantand the method of making which is electrolytically generated in aneconomical manner.

Another object of this invention is to provide an improved disinfectantand the method of making which is suitable for use with an alcoholand/or a detergent.

Another object of this invention is to provide an improved disinfectantand the method of making which may be used on exposed and/orcontaminated surfaces to kill bacteria, virus, fungi and othermicro-organisms.

Another object of this invention is to provide an improved disinfectantand the method of making which may be used on contaminated open woundsand tissue, dermal wound sites and/or lesions of living organisms suchas animals and humans.

Another object of this invention is to provide an improved disinfectantand the method of making which may be used on exposed surfaces in foodprocessing plants, residential, hospital, restaurants, public facilitiesand the like.

The foregoing has outlined some of the more pertinent objects of thepresent invention. These objects should be construed as being merelyillustrative of some of the more prominent features and applications ofthe invention. Many other beneficial results can be obtained by applyingthe disclosed invention in a different manner or modifying the inventionwith in the scope of the invention. Accordingly other objects in a fullunderstanding of the invention may be had by referring to the summary ofthe invention and the detailed description describing the preferredembodiment of the invention.

SUMMARY OF THE INVENTION

A specific embodiment of the present invention is described and shown inthe attached Detailed Description. For the purpose of summarizing theinvention, the invention relates to an improved non-toxicenvironmentally friendly aqueous disinfectant for use as a preventionagainst contamination by potentially pathogenic bacteria, virus andfungi. The improved aqueous disinfectant is suitable for use on exposedsurfaces. In addition, the improved aqueous disinfectant is suitable foruse on dermal wound sites and lesions of living organisms such asanimals and humans. The aqueous disinfectant is pH neutral.

The improved aqueous disinfectant comprises an aqueous solution ofsilver citrate wherein the silver is electrolytically generated in asolution of citric acid and water. The improved aqueous disinfectant hasmany potential uses including bacteria, fungus and viral treatment,water treatment, medical treatment as well as for preserving consumableand non-consumable products.

The improved aqueous disinfectant referred to as electrolyticallygenerated silver citrate appears to be a new composition of matterhaving a formula of AgC₆H₇O₇, and having a tentative chemical name ofsilver dihydrogen citrate. Non-electrolytically generated silver citrateC₆H₅Ag₃O₇.

In another example of the invention, the invention is incorporated intoan aqueous disinfectant in a concentrated form having an extendedshelf-life comprising an aqueous solution of silver citrate wherein thesilver is electrolytically generated in a solution of citric acid inwater.

The aqueous disinfectant may be combined with an alcohol such as ethylalcohol (ETOH) and/or a detergent such as sodium dodecyl sulfate.

The invention is also incorporated into the process of making thedisinfectant comprising the step of electrolytically generating silverin a solution of citric acid and water to formed an aqueous solution ofsilver citrate.

The invention is also incorporated into the process of making silvercitrate, comprising the step of electrolytically generating silver in asolution of citric acid and water to form an aqueous solution of silvercitrate.

The foregoing has outlined rather broadly the more pertinent andimportant features of the present invention in order that the detaileddescription that follows may be better understood so that the presentcontribution to the art can be more fully appreciated. Additionalfeatures of the invention will be described hereinafter which form thesubject matter of the invention. It should be appreciated by thoseskilled in the art that the conception and the specific embodimentsdisclosed may be readily utilized as a basis for modifying or designingother structures for carrying out the same purposes of the presentinvention. It should also be realized by those skilled in the art thatsuch equivalent constructions do not depart from the spirit and scope ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and objects of the invention,reference should be made to the following detailed description taken inconnection with the accompanying drawings in which:

For a fuller understanding of the nature and objects of the invention,reference should be made to the following detailed description taken inconnection with the accompanying drawings in which:

FIG. 1 is a diagram of a first process of making the disinfectant of thepresent invention;

FIG. 2 is a diagram of a second process of making the disinfectant ofthe present invention;

FIG. 3 is an enlarged detailed view of the ion chamber of FIGS. 1 and 2;

FIG. 4 is an enlarged detailed view of an ion chamber suitable formaking the disinfectant of the present invention in a batch process;

FIG. 5 is a magnified view of an electrode configuration suitable formaking the composition of the present invention in a batch process; and

FIG. 6 is a graph illustrating an example of power applied to theelectrode configuration of FIG. 5 for making the composition of thepresent invention.

FIG. 7 is a table illustrating the shelf-life tests for initial samplingintervals;

FIG. 8 is a table illustrating the shelf-life tests for secondarysampling intervals;

FIG. 9 is a table illustrating the efficacy tests against salmonellacholerasuis;

FIG. 10 is a table illustrating the efficacy tests againststaphylococcus aureus; and

FIG. 11 is a table illustrating the efficacy tests against pseudomonasaeruginosa.

Similar reference characters refer to similar parts throughout theseveral Figures of the drawings.

DETAILED DISCUSSION

Process of Making

FIG. 1 is a diagram of a first process 10 of making the disinfectant 14of the present invention. The first process 10 is shown as a continuousprocess of making the disinfectant 14. It should be understood that thefirst process 10 of FIG. 1 is only an example of a process and numerousother variations and/or processes may be utilized to make thedisinfectant 14 of the present invention.

The disinfectant 14 may be used immediately for any suitable applicationsuch as a disinfectant in a water system including cooling towers, hotwater systems, potable water systems, or any other suitable applicationor surface.

The first process 10 comprises a water input conduit 16 for introducingwater 18 from a water source (not shown) to a water treatment unit shownas a reverse osmosis unit 20. The reverse osmosis unit 20 passes thewater 18 from the water input conduit 16 through a semi-permeablemembrane (not shown) for removing impurities from the water. Althoughthe water treatment unit is shown as a reverse osmosis unit 20 it shouldbe understood that various water treatment units may be employed withinthe process shown in FIG. 1. Preferably, the water 18 emanating from thereverse osmosis unit 20 is deionized medically pure water.

The water 18 emanating from the reverse osmosis unit 20 is directed to avalve 30 through a conduit 31. The valve 30 directs the water 18 thougha conduit 32 to a flow control injector 40. A citric acid tank 50contains concentrated citric acid. The concentrated citric acid isdirected by a conduit 51 to a metering valve 60 for metering theconcentrated citric acid into the flow control injector 40. The flowcontrol injector 40 mixes the concentrated citric acid with the water 18to provide a dilute citric acid solution 62. The metering valve 60controls the concentration of the citric acid within the water 18. Thediluted citric acid solution 62 is directed by a conduit 62 into an ionchamber 70.

FIG. 3 is an enlarged detailed view of the ion chamber 70 of FIG. 1. Theion chamber 70 includes a positive and a negative electrode 71 and 72.The positive and negative electrodes 71 and 72 are located in a spacedapart position for enabling the diluted citric acid solution 62 to passbetween the positive and negative electrodes 71 and 72. Each of thepositive and negative electrodes 71 and 72 is fabricated from elementalsilver. Preferably, the positive and negative electrodes 71 and 72 areformed from 99.99990% pure elemental silver.

A direct current power supply 80 includes a positive and a negativeconductor 81 and 82 connected to the positive and negative electrodes 71and 72. The positive and negative electrodes 71 and 72 are spaced aparta suitable distance such as 2.0 to 8.0 centimeters to allow an ioniccurrent flow between the positive and negative electrodes 71 and 72.

Upon energizing the direct current power supply 80, an ion current flowsbetween the positive and negative electrodes 71 and 72. The direct ioncurrent flow between the positive and negative electrodes 71 and 72produces electrolytically free silver ions within the diluted citricacid solution 62. The silver ions react with the citric acid in thediluted citric acid solution 62 to produce the disinfectant 14 of thepresent invention.

The disinfectant 14 is directed by a conduit 86 to a settling tank 90.The settling tank 90 includes an overflow conduit 91 and a drain conduit92. The disinfectant 14 exits the settling tank 90 through the overflowconduit 91. Any precipitated materials from the disinfectant 14 withinthe settling tank 90 fall to the bottom of the settling tank 90. Theprecipitated materials at the bottom of the settling tank 90 may beremoved through the drain conduit 92 to a purge tank 100. Theprecipitated materials in the purge tank 100 may be recycled.

The disinfectant 14 exiting through the overflow conduit 91 from thesettling tank 90 is directed to a particle filter 110. Although theparticle filter 110 may be any suitable filter, preferably the particlefilter 110 is a submicron filter. The filtered disinfectant 14 isdirected to a valve 120 by a conduit 121. The valve 120 directs thefiltered disinfectant 14 to a conduit 122 for discharge from the firstprocess 10.

The filtered disinfectant 14 discharged from conduit 122 may be usedimmediately for any suitable application such as a disinfectant in awater system or any other suitable application. In the event a greaterconcentration of the disinfectant 14 is desired, the disinfectant 14 maybe recirculated for increasing the concentration of the disinfectant 14.

FIG. 2 is a diagram of a second process 10A of making the disinfectant14 of the present in a concentrated form. The second process 10A isshown as a recirculating process of making the disinfectant 14 and forincreasing the concentration of the disinfectant 14. In the concentratedform, the disinfectant 14 may be bottled for use at a later time. Itshould be understood that the second process 10A of FIG. 2 is only anexample of a process and numerous other variations and/or processes maybe utilized to make the disinfectant 14 of the present invention.

In the second process 10A shown in FIG. 2, the valve 30 and 120 are moveinto positions opposite to the positions shown in FIG. 1. The valve 120directs the filtered disinfectant 14 to a conduit 123. The conduit 123is connected through a conduit 130 to the conduit 32 of the valve 30.

The valve 30 directs the filtered disinfectant 14 though the conduit 32to the flow control injector 40. Additional concentrated citric acid isdirected through the metering valve 60 into the flow control injector40. The flow control injector 40 mixes the concentrated citric acid withthe filtered disinfectant 14 to increase the concentration of the citricacid solution 62A.

The citric acid solution 62A is directed into an ion chamber 70 toproduce additional silver ions within the citric acid solution 62A. Thesilver ions react with the citric acid in the citric acid solution 62Ato increase the concentration of the disinfectant 14. The disinfectant14 is passed through the settling tank 90 to exit through the overflowconduit 91. The disinfectant 14 is filtered by the particle filter 110and is directed to the valve 120 by the conduit 121.

The valve 30 and 120 are maintained in positions shown in FIG. 2 tocontinue to recirculate the disinfectant 14 for increasing theconcentration of the disinfectant 14. Upon obtaining the desiredconcentration of the disinfectant 14, the valve 120 may be moved to theposition shown in FIG. 1 to discharge the disinfectant 14 from theconduit 122.

FIG. 4 is an enlarged detailed view of an ion chamber 170 suitable formaking the disinfectant of the present invention in a batch process. Theion chamber 170 includes a positive and a negative electrode 171 and172. Each of the positive and negative electrodes 171 and 172 isfabricated from 99.9999% pure elemental silver.

The positive and negative electrodes 171 and 172 are located in a spacedapart position for enabling the citric acid solution 162 to pass betweenthe positive and negative electrodes 171 and 172. Preferably, thepositive silver electrode 171 is spaced relative to a negative electrode172 a distance sufficient to enable silver ion flow therebetween. Thespacing of the positive and negative electrodes 171 and 172 has beenshown in an exaggerated fashion in FIG. 4. Preferably, a spacing ofapproximately 2.0 to 8.0 mm. has been found to be suitable for the aboveconcentration of citric acid and water.

A direct current power supply 180 includes a positive and a negativeconductor 181 and 182 connected to the positive and negative electrodes171 and 172. Upon energizing the direct current power supply 180, an ioncurrent flows between the positive and negative electrodes 171 and 172.The direct ion current flow between the positive and negative electrodes171 and 172 produces electrolytically free silver ions within the citricacid solution 162. The silver ions react with the citric acid in thecitric acid solution 162 to produce the disinfectant 14 of the presentinvention.

A direct current power supply 180 includes a positive and a negativeconductor 181 and 182 connected to the positive and negative electrodes171 and 172. Upon energizing the direct current power supply 180, an ioncurrent flows between the positive and negative electrodes 171 and 172.The direct ion current flow between the positive and negative electrodes171 and 172 produces electrolytically free silver ions within the citricacid solution 162. The silver ions react with the citric acid in thecitric acid solution 162 to produce the composition 14 of the presentinvention.

FIG. 5 is an enlarged detailed view of the first and second electrodes171 and 172 for the batch process shown FIG. 4. The first and secondelectrodes 171 and 172 are provided with through apertures 173 and 174.The power supply 180 is connected through electrical connectors 181 and182 to the first and second electrodes 171 and 172.

An electrode hanger 190 comprises a depending member 192 having afastener 194 connected to an upper end of the depending member 192. Thefastener 194 is connectable to a support (not shown) for supporting thedepending member 192 within the ion chamber 170 shown in FIG. 4. A lowerend of the depending member 192 is connected to a cross member 196.Opposed distal ends of the cross member 196 are inserted within thethrough apertures 173 and 174 of the first and second electrodes 171 and172 for supporting the first and second electrodes 171 and 172 withinthe ion chamber 170 shown in FIG. 4.

The sliding relationship of the first and second electrodes 171 and 172on the cross member 196 enables the rapid change of spacing between thefirst and second electrodes 171 and 172 depending upon the desiredoperational parameters of the batch processing shown in FIG. 4. Itshould be appreciated by those skilled in the art that FIG. 5 is merelyan example of one system for suspending the first and second electrodes171 and 172 and that numerous other structures may be incorporated forsuspending the first and second electrodes 171 and 172 for forming thepresent invention.

FIG. 6 illustrates a waveform of the electrical power from the powersupply 180 applied to the first and second electrodes 171 and 172 forthe batch processing shown in FIGS. 4 and 5. The waveform of theelectrical power from the power supply 180 has a peak voltage of 24volts and with an intermittent voltage polarity reversal of every 15seconds. The current density between the first and second electrodes 171and 172 may be changed by varying of the peak voltage applied to thefirst and second electrodes 171 and 172, or varying the size of thefirst and second electrodes 171 and 172 or varying the spacing betweenthe first and second electrodes 171 and 172. Preferably, the currentdensity between the first and second electrodes 171 and 172 is equal toor greater than 0.100 amperes per square inch.

However, it should be understood by those skilled in the art thatnumerous variations in the size and/or spacing of the first and secondelectrodes 171 and 172 and numerous variations in the peak voltage andnumerous variations in the timing sequence of the intermittent voltagepolarity reversal may be incorporated in the process of forming thecomposition 14 of the present invention which should be within the levelof those skilled in the ionization art.

The liquid located between the first and second electrodes 71 and 72 ofFIG. 3 is flowing through the ion chamber 70. In contrast to the dynamicliquid flow between the first and second electrodes 71 and 72 shown inFIG. 3, the liquid located between the first and second electrodes 171and 172 of FIGS. 4 and 5 is essentially static. It has been found thatan intermittent voltage polarity reversal between the first and secondelectrodes 171 and 172 of FIGS. 4 and 5 increases the output of thegeneration of the composition 14 in the batch processing. Although theexact mechanism is not totally understood, is believed that theintermittent voltage polarity reversal increases the circulation of ionsbetween the first and second electrodes 171 and 172 and/or dissipatesany concentration of gases and/or any concentrations of the composition14 located in proximity to the respective first and second electrodes171 and 172.

The process of making a composition comprises electrolyticallygenerating silver ions in a solution of citric acid and water to form anaqueous solution of silver citrate. Preferably, the solution of citricacid and water comprises a solution greater than 1.0% and up to 30%citric acid in water by volume. A potential difference of 12 volts to 50volts provides a flow of silver ions in the range of 0.1 amperes to 0.5amperes per square inch. A more fuller explanation of the content of thesolution within the ion chamber 170 will be described in greater detailhereinafter.

The prior art has established in that the generation of both silver ionsand copper ion in water provides the best disinfectant properties. Thecombination of silver ions and copper ions provides superiordisinfecting properties than either silver ions alone or copper ionsalone. This synergistic effect of silver ions and copper ions in waterhas been well established by the prior art.

In contrast to this established prior art, the disinfectant of thepresent invention is formed in a solution of citric acid and waterrather than water alone. Additionally, the disinfectant of the presentinvention has superior properties with only silver ions alone ratherthan the combination of both silver ions and copper ions. The silverions of the present process react with the citric acid to form a silvercitrate. The silver citrate provides superior disinfectant propertiesover the prior art process of generating silver and copper ions inwater.

In further contrast to the established prior art, the disinfectant ofthe present invention has a stable ionic form having an extended usefulshelf-life. The useable shelf-life of the disinfectant of the presentinvention enables the aqueous disinfectant solution to be packaged in anaqueous concentrate form.

Composition

The improved disinfectant is an aqueous solution of silver citratewherein the silver is electrolytically generated in a solution of citricacid and water. The silver citrate formed in accordance with the aboveprocess has different characteristics than other forms of silvercitrate.

Concentrations of 0.1% silver citrate by volume have been formulated inaccordance with the above process. A concentration of 0.1% silvercitrate by volume corresponds to 1000 parts per million (ppm). Theconcentration of 0.1% silver citrate was formed in a solution of citricacid and water comprises approximately 20.0% citric acid by volume.Higher concentration of the silver citrate are believed to be obtainableby the above process. It appears the higher the concentration of citricacid in water, the higher the concentration of silver citrate formed bythe above process.

The Merck Index, Eleventh Edition (1989) page 1348 states that silvercitrate is soluble in 3500 parts water. A concentration of 1 to 3500corresponds to 285 parts per million (ppm). Obviously, the silvercitrate formed in accordance with the above process has differentsolubility than other forms of silver citrate.

Nuclear magnetic resonance tests (1H NMR) were preformed on the silvercitrate formed in accordance with the above process and a blank citricacid sample. The samples showed an overwhelming excess of citric acid,with little or no other anions present. It is postulated the Ag must bein the form of the cation Ag+ complexed with the citric acid. It istheorized the empty 5 s orbital of Ag+ overlaps with the delocalized δbond on one of the carboxyl groups of citric acid. The citric acid anionis the counterion for this complex ion (Ag(CA)x)+l.e. (CA). CA is citricacid or is (C₆H₈O₇—H₂O). Another possibility is a zwitterion, where thenegative charge is on the complex itself, (Ag+CA−) where the totalcharge of the complex is neutral. Either or both of these species mayexist in the silver citrate formed in accordance with the above process.Multiple complexation to Ag+ is also possible.

A second formulation of the improved disinfectant of the presentinvention includes the addition of an alcohol. In one example of thesecond formulation of the improved disinfectant, ethyl alcohol (ETOH) isadded in an approximate amount of 20% by volume. However, it should beunderstood that other types of alcohols may be added to the secondformulation of the improved disinfectant of the present invention.

A third formulation of the improved disinfectant of the presentinvention includes the addition of a detergent. In one example of thethird formulation of the improved disinfectant, sodium dodecyl sulfateis added in an approximate amount of 0.1% by volume.

Silver Dihydrogen Citrate

Experiments were conducted by David Pullman, Jennifer Beyer, and GregGidofalvi Department of Chemistry, San Diego State University, SanDiego, Calif. 92182-1030 to determine the physical form of silver incomposition referred to as electrolytically generated silver citrate inthis specification. A report of the finding was issued on Jun. 24, 2002and is incorporated by reference into the present specification.

The experiments indicated the silver exists predominantly in the form ofa weakly-bound complex in which one silver ion is weakly-bound to onecitrate ion. The chemical formula of this complex was indicated to beAgC₆H₇O₇. Some silver ions are bound to two citrate ions, and some ofthe silver may exist as “free” silver ions, but the evidence suggeststhat the large majority of silver exists in a complex containing onesilver ion and one citrate ion.

The electrolytically generated silver citrate complex, AgC₆H₇O₇, canalso be considered a salt. It appears the electrolytically generatedsilver citrate complex, AgC₆H₇O₇, is a new composition of matter havinga tentative chemical name of silver dihydrogen citrate.Non-electrolytically generated silver citrate C₆H₅Ag₃O₇.

The tentative name silver dihydrogen citrate has been assigned to theelectrolytically generated silver citrate by analogy to other knownsalts in which the anion—in this case, citrate—can bind to more than onemetal ion. For example, the phosphate anion has three binding sites andcan bind to one, two, or three sodium ions. When the phosphate anionbinds one sodium ion, the salt is called sodium dihydrogen phosphatebecause the other two binding sites are taken by hydrogen.)

The conclusion that the silver exists predominantly in the form of aweakly-bound complex was based on two sets of experiments, namely (1)electrospray ionization mass spectroscopy and (2) electrochemical. Theimplication of the electrochemical results was that all the silverexists as “free” silver ions, whereas the electrospray mass spectroscopyresults indicate that most, if not all, the silver exists in a boundcomplex. The answer likely has to do with the definition of “free ion.”If a salt, such as sodium chloride, is dissolved in water, the sodiumand chloride ions are typically considered as being “free” ions insolution; however, these ions are actually bound to water molecules, andthe bond strength is somewhat appreciable.

The implication of these considerations is that in electrolyticallygenerated silver citrate (silver dihydrogen citrate), the silver ionlikely exists as a weakly-bound complex with citrate. The bond betweenthe silver and citrate is sufficiently weak that the complex easilydissociates in the electrochemical setup, but it is sufficiently strongthat the complex survives in the electrospray mass spectrometerexperiments.

Shelf-Life Study

The copper and silver ions in the prior art aqueous solution have only alimited stable ionic life. After a limited time, the copper and silverions in the prior art aqueous solution form complexes with otherelements thus diminishing the concentration of the copper and silverions within the aqueous solution.

A significant difference of the disinfectant of the present invention isthe stable life of the silver citrate. The present invention provides anaqueous disinfectant solution having a stable ionic form having anextended useful shelf-life. The extended useful shelf-life of thedisinfectant of the present invention enables the disinfectant to bepackaged in an aqueous concentrate form.

A series of tests was preformed on the following formulations.

1. Silver and Citric Acid (1.0% citric acid solution/pH 6.0)

2. Silver and Citric Acid (5.0% citric acid solution/pH 6.0)

3. Silver and Citric Acid (10% citric acid solution/pH 6.0)

The silver and citric acid formulations were prepared using 100/100silver:silver electrodes. The electrodes were immersed in 1.0, 5.0 and10% citric acid solutions and a current was applied for approximatelytwo hours. The solutions were stored for 24 hours to allow forprecipitation. The solutions were filtered using #2 Whatman filterpaper. The final pH was adjusted to 6.0 with sodium carbonate and sodiumbicarbonate.

FIG. 7 is a table illustrating the results of the shelf-life test forthe initial shelf-life sampling intervals. The initial intervals for theinitial shelf-life sampling intervals of the disinfectant were 1 week, 2weeks, 3 weeks and 4 weeks. FIG. 7 illustrates that silver citrate isnot stable at high concentrations in the 1.0% citric acid solution. The300 ppm silver citrate did not remain in the 1.0% citric acid solution.However, the 300 ppm silver citrate was stable in the 10% citric acidsolution.

FIG. 8 is a table illustrating the results of the shelf-life test forsecondary shelf-life sampling intervals. The secondary intervals for thesecondary shelf-life sampling intervals of the disinfectant were 0weeks, 7 weeks, 14 weeks and 21 weeks. FIG. 8 also illustrates thatsilver citrate is not stable at high concentrations in the 1.0% citricacid solution. Conversely, the silver citrate was stable in both the 5%and 10% citric acid solutions.

The results seen in FIG. 8 for week 21 confirm the stability of thesilver citrate in the 5.0% and 10% citric acid solutions. The stabilityof the silver citrate in the 1.0% citric acid solution experiencedsignificant reductions during the last phase of the study. The minimumconcentration of the citric acid solution is therefore some valuegreater than 1.0% and less than 5.0%. The maximum concentration of thecitric acid in the aqueous solution has not been determined by test.However, it is believed that the maximum concentration of the citricacid in the aqueous solution much greater than 20.0%. It is also evidentfrom these results, that the higher the concentration of the citric acidin the aqueous solution, the greater the concentration of silver ionsthat can be stabilized.

Laboratory Study

In order to establish the effectiveness of the improved disinfectant ofthe present invention, laboratory tests were performed against varioustest microorganisms. The test microorganisms considered were (a)pseudomonas aeruginosa strain ATCC 15442, (b) Salmonella cholerasuisstrain ATCC 10708 and (c) Staphylococcus aureus strain ATCC 6538.

The inoculum level for each of the test microorganisms were establishedin a similar manner. Test strains were grown individually at 35° C. for24 hr. The cells were harvested by centrifugation at 10,000×g for 10minutes and washed twice with Butterfield's Phosphate Buffer (BPB of pH7.2). The cells were resuspended in the Butterfield's Phosphate Bufferto obtain a cell suspension of approximately 1.0×10⁸ CFU/mL for eachmicroorganism (target inoculum levels were approx. 10⁶ in the final testsolution).

The test microorganisms considered were tested at uniform samplingintervals, The sampling intervals selected were (a) 15 seconds (ethanoltrials only), (b) 1 minute, (c) 5 minutes, (d) 10 minutes and (e) 30minutes.

Five compounds were tested against the test microorganisms. The fivecompounds tested were (a) silver and citric acid (4.27 ppm in a 0.1%citric acid solution), (b) copper and citric acid (4.07 ppm in a 0.1%citric acid solution), (c) citric acid (0.1% citric acid solution), (d)silver (4.08 ppm), citric acid (0.1%) and ethanol (20%) and (e) Ethanol(20%).

The silver and citric acid (4.27 ppm in a 0.1% citric acid solution) wasprepared using 100/100 silver:silver electrodes. The electrodes wereimmersed in a 0.1% citric acid solution and current was applied forapproximately two hours. The solution was stored for 24 hours to allowfor precipitation. The solution was filtered using No. 2 Whatman filterpaper. The final pH was adjusted to 7.0. The concentration tested had asilver concentration of 4.27 mg/L.

The copper and citric acid (4.07 ppm in a 0.1% citric acid solution) wasprepared using 100/100 copper:copper electrodes. The electrodes wereimmersed in a 0.1% citric acid solution and current was applied forapproximately two hours. The solution was stored for 24 hours to allowfor precipitation. The solution was filtered using #2 Whatman Filterpaper. The final pH was adjusted to 7.0. The concentration tested had acopper concentration of 4.07 mg/L (as measured by ICAP).

The citric acid (0.1% citric acid solution) was prepared using deionizedwater. The pH was adjusted to 7.0.

The silver (4.08 ppm), citric Acid (0.1%) and ethanol (20%) was preparedusing 100/100 silver:silver electrodes. The electrodes were immersed ina 0.1% citric acid solution and current was applied for approximatelytwo hours. The solution was stored for 24 hours to allow forprecipitation. The solution was filtered using #2 Whatman filter paper.The final pH was adjusted to 7.0. The solution was diluted with ethanolto yield a concentration of 4.08 mg/L silver in a 20% ethanol solution.

The Ethanol (20%) was prepared with by diluting Reagent grade ethanolwith deionized water to make the appropriate dilution.

The test microorganisms were tested in accordance with the followingtest procedures. Duplicate trials were conducted for each test variable.Ninety nine volumes of the test solutions in 250 mL Erlenmeyer flaskswere prepared from sterilized deionized water. The solutions wereinoculated separately with one mL of 24 hour culture from each of thetest strains to yield a flask inoculum level of approximately 1.0×10⁶CFU/mL. The actual count for each of the microorganisms are set forth inFIGS. 7-9.

Solutions were mixed well and kept under constant agitation. Samples of1.0 mL were removed at the above specified time intervals and placedinto 9.0 mL Neutralization Broth media (Difco) to yield an initialdilution of 1:10. All samples were serially diluted in the Butterfield'sPhosphate Buffer solution (BPB) and plated onto Tryptic Soy Agar (TSA)in duplicate using the pour plate technique. Percent reductions werecalculated for each test solution against each test strain.

The results of the laboratory study can be seen in FIGS. 7-9. For alltests which utilized either copper or silver ions, concentratedsolutions were prepared 24 hours prior to the beginning of the study.Solutions were filtered and determinations for ion content were made.From these stock solutions (copper ion concentration as measured by ICAPand silver ion concentration as measured by Atomic Absorption analysis),final working solutions were made. The target ion concentration for bothcopper and silver was 5.0 mg/L.

FIG. 9 is a table illustrating the efficacy tests against salmonellacholerasuis. The trials that utilized 20% ethanol showed a slow, butcomplete disinfection. The ethanol solution has an approximate 1.0 log₁₀reduction after one minute. Near complete disinfection was seen after 30minutes of contact time. Of the three organisms tested, salmonellacholerasuis was the one most effected by the ethanol disinfectant. Thecopper:citric acid was not effective in disinfecting salmonellacholerasuis at any of time periods. The citric acid solution wasslightly more effective in reducing the number of salmonellacholerasuis, achieving a 1.0 log₁₀ reduction at the 30 minute timeperiod. Both silver:citric acid and silver:citric acid with ethanolexhibited a 6.0 log₁₀ reduction over the course of the 30 minute trial.The silver:citric acid solution showed a 5.0 log₁₀ reduction within thefirst 5 minutes and a greater 6.0 log₁₀ reduction at the 10 minute timeperiod. Silver:citric acid with ethanol appeared to be the mosteffective, exhibiting a 2.36 log₁₀ reduction within in the first minuteand a greater than 6.0 log₁₀ reduction within the first 5 minutes ofcontact.

FIG. 10 is a table illustrating the efficacy tests againststaphylococcus aureus. This table indicates a different reaction for the20% ethanol against staphylococcus aureus as compared to salmonellacholerasuis. No significant reduction was seen between 15 seconds and 30minutes. Neither citric acid nor copper:citric acid was effectiveagainst staphylococcus aureus. Neither of the aforementioned formulaswere able to significantly reduce the number of staphylococcus aureusorganisms present within the 30 minute time period. However, bothsilver:citric acid and silver:citric acid with ethanol exhibited a 6.0log₁₀ reduction over the course of the 30 minute trial. Thesilver:citric acid solution showed a 3.0 log₁₀ reduction within thefirst 10 minutes and a greater than 6.0 log₁₀ reduction at the end of 30minutes. Silver:citric acid with ethanol appeared to be the mosteffective, exhibiting a 2.36 log₁₀ reduction within the first minute anda greater than 6.0 log₁₀ reduction within the first 5 minutes ofcontact.

FIG. 11 is a table illustrating the efficacy tests against pseudomonasaeruginosa. The seen in this table for pseudomonas aeruginosa, indicatesimilar results as those seen for that used staphylococcus aureus. Forthe 20% ethanol trials, no significant reduction was seen between 15seconds and 30 minutes. This same trend was recorded for citric acid andcopper:citric acid. Both silver:citric acid and silver:citric acid withethanol exhibited near or greater than 6.0 log₁₀ reductions over thecourse of the 30 minute trial. The silver:citric acid solution showed a2.49 log₁₀ reduction at the 10 minute time period and a greater than5.70 log₁₀ reduction at the end of 30 minutes. Silver citric acid withethanol showed the best disinfection against pseudomonas aeruginosa,mirroring the results seen with the other two organisms. A greater than6.0 log₁₀ reduction was recorded at the 5 minute sampling period.

Field Trial Results

The improved disinfectant has been tested in preliminary veterinaryfield trials to establish the effectiveness of the present invention.The veterinary field trial test were conducted by licensed veterinarianson equine species. The improved disinfectant was tested on contaminatedopen, non-healing tissue and wounds. The open, non-healing wounds weretreated with wet dressings or by spraying the improved disinfectant ontothe wound.

The disinfectant has been tested on dermal lesions both contaminated andinfected with gram negative and gram positive bacteria. The results haveshown that this formulation exhibits superior performance as compared toavailable disinfectant products currently on the market. Thedisinfectant formulation has shown to be very efficacious for irrigatingdeep wounds and abscesses without damage to tissue. Decreased healingtime and reduction in scar formation have been observed repeatedlyduring the study. The disinfectant appears to promote healthygranulation without excessive fibrosis.

The disinfectant has been used as a surface disinfectant and thereforehas shown best results with extended contact with the contaminatedtissue. On surface wounds, best results are obtained with “wet dressing”or frequent spray applications for dermal surfaces not amenable toapplied dressing. Drained abscesses are flushed, the disinfectantsolution is held in the cyst, then drained and again filled and agitatedfor 2-3 minutes before allowing to drain. Deep wounds closed with drainshave shown rapid healing time and reduced draining when flushed with thedisinfectant. An additional use for the disinfectant may be as a uterineflush for bacterial and/or fungal/yeast infection. Preliminary resultswith this application have shown to be very promising.

Hard Surface Disinfectant

The electrolytically generated silver citrate has been found effectiveas a hard surface disinfectant with direct food contact for thefollowing:

-   -   Pseudomonas aeruginosa strain ATTC 15442,    -   Salmonella choleraesuis strain ATCC 10708    -   Staphylococcus aureus strain ATCC 65328    -   E. coli 0157:H7    -   E. coli ATCC 11229    -   listeria monocytogenes ATCC 11543    -   Enterococcus faecium ATCC 6569    -   Human immunodeficient Virus Type 1    -   Herpes simplex virus type 1    -   Poliovirus type 2    -   Influenza A    -   Rhinovirus        The tests on the above were conducted by independent testing        laboratories in compliance with the U.S. Environmental        Protection Agency Good laboratory Practice (GLP) regulations set        forth and 40 CFR Section 160. The final reports forming the        basis for the above results are identified hereinafter with the        totality of these reports being incorporated by reference into        the present specification.

Based on the above results, it is believed electrolytically generatedsilver citrate will be effective as a hard surface disinfectant withdirect food contact against SARS. Further test will be conducted toverify the efficacy of the electrolytically generated silver citrateagainst SARS.

Water Treatment

The electrolytically generated silver citrate has been found effectivefor the treatment of water such as:

-   -   Potable Water    -   Municipal Water systems    -   Swimming Pool/Spa treatment    -   Cooling Systems    -   Cooling Tower Biocide and Biofilm Control

The electrolytically generated silver citrate has been found to be aneffective treatment for microbicides used in cooling systems such aslegionella pneumophila Tests were conducted by independent testinglaboratories in compliance with the U.S. Environmental Protection AgencyGood laboratory Practice (GLP) regulations set forth and 40 CFR Section160. The final reports forming the basis for the above results areidentified hereinafter with the totality of these reports beingincorporated by reference into the present specification.

The efficacy of electrolytically generated silver citrate was test on(1) Legionella pneumophila serogroup 1, (2) heterotrophic bacteria (HBC)in biofilm and planktonic phases and (3) E. coli was also tested atelectrolytically generated silver citrate concentrations of 50 and 100ppb silver.

All three concentrations 3 ppm 15 ppm and 30 ppm passed the ASTM E645-97Standard Test Method for Efficicay of Microbicides used in coolingsystems when L. pneumophila was exposed to the test material for 3, 7and 24 hours at ambient room temperature.

Electrolytically generated silver citrate at 72 ppb was as effective assilver chloride solution (80 ppb) in eradicating laboratory grownLegionella pneumophila serogroup 1 in vitro. Electrolytically generatedsilver citrate silver solution killed Legionella in biofilm andplanktonic samples. Electrolytically generated silver citrate appearedto be more effective against biofilm-associated Legionella thanplanktonic Legionella. The electrolytically generated silver citratesilver solution achieved a 3 log reduction of Legionella in the biofilmversus a 1.5 log reduction against planktonic Legionella.

The electrolytically generated silver citrate silver solution did notsignificantly reduce heterotrophic bacteria in the model plumbingsystem. This finding is similar to other biocides tested in the modelplumbing system.

Bacteria

The electrolytically generated silver citrate has been found to be aneffective killing agent of bacteria Test have determined the efficacy of30 ppm electrolytically generated silver citrate as follows:

BACTERIA KILL TIME Proprionibacterium acnes ATCC 6921 15-secondsPseudomonas aeruginosa ATCC 15422 30-seconds Staphylococcus aureus ATCC6538 30-seconds Salmonella cholerasuis ATCC 10708 30-seconds Listeriamonocytogenes ATCC 19111 30-seconds E. coli 0157 ATCC 43888  2-minuteEnterococcus facium (VRE)ATCC 700221  2-minute Staphylococcus aureus(MRSA) ATCC 700698  2-minuteThe electrolytically generated silver citrate has been found to beeffective against both gram positive and gram negative bacterial makingthe electrolytically generated silver citrate ideal for treating traumaand wounds in both human and veterinary use. The non-toxic nature of theelectrolytically generated silver citrate make the disinfectant suitablefor use not only as a topical agent for humans but also for use as amouthwash or a toothpaste. It is believed the electrolytically generatedsilver citrate will be safe and effective for the treatment of vaginitisand further test will be conducted to verify this belief. It is alsobelieved that the electrolytically generated silver citrate will beeffective as a hard surface disinfectant with direct food contactagainst SARS.Fungus

The electrolytically generated silver citrate has been found to be aneffective killing agent of fungus. Test have determined the that 30 ppmelectrolytically generated silver citrate kills TrichophytonMentagrophytes ATCC 9533 after a after 10 minute exposure. Theelectrolytically generated silver citrate has been found to be aneffective killing agent of fungus associated with open wounds.

It is believed the electrolytically generated silver citrate will besafe and effective for the treatment of athlete's foot, toenail fungusand tinea infection although further test need to be conducted to verifythis belief.

Virus

The electrolytically generated silver citrate has been found to be aneffective killing agent of various viruses. Test have determined theefficacy of 30 ppm electrolytically generated silver citrate as follows:

VIRAL KILL TIME HIV type1, Strain HTLV = IIIB 30-second Herpes simplextype I ATCC VR-733, Strain F.(1)  1-minute Rhinovirus R37 ATCC VR-1147,Strain 151-1 10-minute Influenza A ATCC VR-544, Hong Kong Strain10-minute Poliovirus type 2 ATCC VR-1002, Strain Lansing 10-minute

It is believed the electrolytically generated silver citrate will besafe and effective for the treatment of additional viruses althoughfurther test need to be conducted to verify this belief. It is alsobelieved the electrolytically generated silver citrate will be safe andeffective for the treatment of chancre sores and other dermal treatment.

Preservation

The electrolytically generated silver citrate has been found to be aneffective agent for reserving various products against degradation dueto the actions of various bacteria, fungi and the like. The non-toxicnature of electrolytically generated silver citrate makes thecomposition suitable for preserving both consumable and non-consumableproducts.

The electrolytically generated silver citrate may be included in theformulation of non-consumable products in the liquid, gel, cream, pasteor solid form. Some of these products may include but not limited to allforms such as water based coatings, paints, glues, cosmetic and shavingcreams, cosmetic gels and lotions, cosmetic pastes, lipsticks and thelike.

The electrolytically generated silver citrate may be used to rinsenon-consumable products for preserving the life of the non-consumableproducts. Some of these products may include but not limited to freshflowers and the like.

The electrolytically generated silver citrate may be included in theformulation of consumable food products in various forms. Some of theseconsumable products may include canned, freeze dried, bottled andpackaged food products of all descriptions including but not limited tomeats, seafood, poultry fruits, vegetables, soft drinks, fruits, jams,citrus juices and the like.

The electrolytically generated silver citrate may be used to rinseconsumable products for preserving the life of the consumable foodproducts. These consumable products may include but not limited to freshfood products meat, seafood, poultry, fresh vegetables and fruits.

Tests have determined the efficacy of 30 ppm electrolytically generatedsilver citrate on a matrices of alfalfa sprouts, lettuce, bananas,melons, apples, strawberries, fish fillets and shrimp.

The data generated in the study concluded that fruits, vegetables, fishand shrimp exposed to approximately 5 ppm of electrolytically generatedsilver citrate and water for 5 seconds, then allowed to drip dry for 10seconds, then rinsed in 0.1 ppm of electrolytically generated silvercitrate for 5 seconds, eliminated 99.99% of the total bacteria present.Silver residuals detected on the produce were maintained withinallowable tolerances for food grade products.

Agricultural industrial eliminate tests demonstrate effectiveness of theelectrolytically generated silver citrate by significantly reducingpathogenic bacterial populations, biofilms, and decreasing live amortality and shrimp live a raising tanks. Further testing of ask nowincludes the use as a disinfectant and preventive speech and seafoodpackaging as actually not produce carcinogenic pot byproducts.

Delivery Mechanisms

The electrolytically generated silver citrate may be applied ordelivered to the intended use in various way and manners. Theelectrolytically generated silver citrate may be applied by wipes,towelettes, bandages, dressings or may be applied by swabbing ormopping.

The electrolytically generated silver citrate may be applied by sprayingor immersion of the product within the electrolytically generated silvercitrate. The electrolytically generated silver citrate may be added to aproduct by volumetric fluid addition or may be included in theformulation of a liquid, solid, lotion, cream, gel or a dissolvablesolid such as a soap or lipstick.

Test Reports

The following is a list of test reports conducted by independent testinglaboratories in compliance with the U.S. Environmental Protection AgencyGood laboratory Practice (GLP) regulations set forth and 40 CFR Section160. The final reports forming the basis for the above results areidentified hereinafter with the totality of these reports beingincorporated by reference into the present specification.

Protocol Title: Virucidal Efficacy of a Disinfectant for Use onInanimate Enviromental Surfaces Virus: Human Immunodeficient Virus Type1 Product Identity: Axen (EPA # 72977-2), the 30 ppm use dilution ofAxenohl (EPA # 72977-1), a 2400 ppm concentrate Protocol Number:IMS99111501.HIV Project Number: 12305 Study Completion Date: Dec. 20,2001 Performing Laboratory: AppTec Laboratory Service, 2540 ExecutiveDrive, St. Paul, MN 55120 Protocol Title: Virucidal Efficacy of aDisinfectant for Use on Inanimate Enviromental Surfaces Virus: Herpessimplex Virus Type 1 Product Identity: Axen (EPA # 72977-2), the 30 ppmuse dilution of Axenohl (EPA # 72977-1), a 2400 ppm concentrate ProtocolNumber: IMS01011002.HSV Project Number: 12609 Study Completion Date:Feb. 12, 2002 Performing Laboratory: AppTec Laboratory Service, 2540Executive Drive, St. Paul, MN 55120 Protocol Title: Virucidal Efficacyof a Disinfectant for Use on Inanimate Enviromental Surfaces Virus:Poliovirus Type 2 Product Identity: Axen (EPA # 72977-2), the 30 ppm usedilution of Axenohl (EPA # 72977-1), a 2400 ppm concentrate ProtocolNumber: IMS01011002.POL Project Number: 12608 Study Completion Date:Feb. 12, 2002 Performing Laboratory: AppTec Laboratory Service, 2540Executive Drive, St. Paul, MN 55120 Protocol Title: Virucidal Efficacyof a Disinfectant for Use on Inanimate Enviromental Surfaces Virus:Influenza A Product Identity: Axen (EPA # 72977-2), the 30 ppm usedilution of Axenohl (EPA # 72977-1), a 2400 ppm concentrate ProtocolNumber: IMS01121301.FLU Project Number: 12465 Study Completion Date:Jan. 17, 2002 Performing Laboratory: AppTec Laboratory Service, 2540Executive Drive, St. Paul, MN 55120 Protocol Title: AOAC Use Dilution -Carrier confirmation Staphylococccus aureus (MRSA) ATCC 700698Enterococcus fascium (VRE) ATCC 700221 Listeria monocytogenes ATCC19111Escherichia coli OH ATCC 43886 Product Identity: Axen (EPA # 72977-2),the 30 ppm use dilution of Axenohl (EPA # 72977-1), a 2400 ppmconcentrate Protocol Number: 200135303-01 Project Number: 197155 StudyCompletion Date: Jan. 10, 2002 Performing Laboratory: NelsonLaboratories Inc., 6289 South Redwood Lake City, UT 84123 ProtocolTitle: Kill Time Study For Propionibacterium Acne Product Identity: Axen(EPA # 72977-2), the 30 ppm use dilution of Axenohl (EPA # 72977-1), a2400 ppm concentrate Protocol Number: 200135201-01 Project Number:197156 Study Completion Date: Feb. 5, 2002 Performing Laboratory: NelsonLaboratories Inc., 6289 South Redwood Road, Salt Lake City, UT 84123Protocol Title: Fungicidal Activity Of A Disinfectant TrichophytonMentagrophytes ATCC 9533 Product Identity: Axen (EPA # 72977-2), the 30ppm use dilution of Axenohl (EPA # 72977-1), a 2400 ppm concentrateProtocol Number: 200124703-03 Project Number: 197157 Study CompletionDate: Jan. 11, 2002 Performing Laboratory: Nelson Laboratories Inc.,6289 South Redwood Road, Salt Lake City, UT 84123 Protocol Title:Evaluation of Axen For Residual Activity Product Identity: Axen (EPA #72977-2), the 30 ppm use dilution of Axenohl (EPA # 72977-1), a 2400 ppmconcentrate Protocol Number: 2001042001 Project Number: 197158 StudyCompletion Date: Feb. 8, 2002 Performing Laboratory: Nelson LaboratoriesInc., 6289 South Redwood Road, Salt Lake City, UT 84123 Protocol Title:AOAC Use Dilution - Carrier confirmation Pseudomonas aeruginosa strainATTC 15442, Salmonella cholerasuis strain ATCC 10708 Staphylococccusaureus strain ATCC 65328 Product Identity: Axen (EPA # 72977-2), the 30ppm use dilution of Axenohl (EPA # 72977-1), a 2400 ppm concentrateProtocol Number: 200126906-02 Project Number: 194972 Study CompletionDate: Jan. 9, 2002 Performing Laboratory: Nelson Laboratories Inc., 6289South Redwood Road, Salt Lake City, UT 84123

Although the invention has been described in its preferred form with acertain degree of particularity, it is understood that the presentdisclosure of the preferred form has been made only by way of exampleand that numerous changes in the details of construction and thecombination and arrangement of parts may be resorted to withoutdeparting from the spirit and scope of the invention.

1. A consumable food product that has been treated with a compositioncomprising silver dihydrogen citrate and citric acid in an amountsufficient to obtain at least a 2.36 log₁₀ reduction in the number ofmicroorganisms present.
 2. The consumable food product of claim 1wherein said amount is sufficient to obtain at least a 5.0 log₁₀reduction in the number of organisms present.
 3. The consumable foodproduct of claim 2 wherein said amount is sufficient to obtain at leasta 6.0 log₁₀ reduction in the number of organisms present.
 4. Theconsumable food product of claim 1 which is meat, seafood, poultry, orvegetable.
 5. The consumable food product of claim 1 which is canned,freeze dried, or bottled.
 6. The consumable food product of claim 1wherein the microorganisms comprise bacteria.
 7. The consumable foodproduct of claim 1 wherein the microorganisms comprise fungi.
 8. Theconsumable food product of claim 1 wherein the microorganisms comprisevirus.
 9. The consumable food product of claim 1 wherein the compositionfurther comprises an alcohol.
 10. The consumable food product of claim 9wherein the alcohol is ethanol.
 11. A consumable food product which hasbeen treated by a process comprising applying to the consumable foodproduct an aqueous disinfectant solution comprising from 5 ppm to 30 ppmof silver dihydrogen citrate and from 5% to 10% citric acid, therebydisinfecting the consumable food product.
 12. A consumable food productwhich has been treated by a process, comprising: (a) exposing theconsumable food product to from 5 ppm to 30 ppm of silver dihydrogencitrate for at least 5 seconds; (b) allowing the food product to dripdry; and (c) rinsing the food product with at least 0.1 ppm of silverdihydrogen citrate; thereby eliminating 99.99% of the total bacteriapresent.
 13. A consumable food product formulated to include acomposition that comprises an amount of silver dihydrogen citrate andcitric acid sufficient to obtain at least a 2.36 log₁₀ reduction in thenumber of microorganisms present.
 14. The consumable food product ofclaim 13 wherein said amount is sufficient to obtain at least a 5.0log₁₀ reduction in the number of organisms present.
 15. The consumablefood product of claim 14 wherein said amount is sufficient to obtain atleast a 6.0 log₁₀ reduction in the number of organisms present.
 16. Theconsumable food product of claim 13 which is meat, seafood, poultry,vegetable, soft drink, fruit, jam, or citrus juice.
 17. The consumablefood product of claim 13 which is canned, freeze dried, or bottled.